194 The Beneficial and Injurious Influences of Fungi. 



but the biological connection between the three forms of the 

 pest was not suspected until Professor De Bary in 1864 proved 

 by cultures that they were three stages in the life history of the 

 fungus plant Puccinia graminis. 



The wild barberry is absent from this district but the Rust 

 disease is very prevalent, and there is still some uncertainty 

 how the first gets over the winter months under these circum- 

 stances. Experts are of opinion that the uredo or summer 

 spores perpetuate the disease by infecting grasses in sheltered 

 places and perhaps by the mycelium of the uredospore lying 

 dormant in the grain. 



Nearly two hundred species of Rusts have this heteroecious 

 mode of life. 



The Bunt in Wheat ( Tilletia Tritici) is another pest which 

 unlike the Rust completes its life-cycle on the same plant, 

 infecting it at an early period and growing up through the 

 season in the tissues of its host, appearing at harvest as black 

 spore masses within the chaff. When this sooty mass is 

 bruised, it emits a disagreeable fishy odour which is often 

 perceptible in the holds of wheat-laden ships, indicating its 

 presence in the wheat-growing countries abroad. 



The infection takes place whilst the plant is in the seedling 

 stage and it is noticed that where a plant is infected, it is always 

 found that every ear of the plant and every grain in each 

 ear is destroyed. This would not always be the case if the 

 plant was infected at maturity by spores conveyed by the 

 wind or other agencies. 



The disease is more prevalent in spring-sown than in autumn 

 sown corn, the reason being that the late autumn weather is 

 not so favourable to spore germination as the spring, and in 

 the case of autumn-sown wheat the young plant by springtime 

 is proof against infections. 



Gerard the botanist, writing in 1597, on the pests of the 

 Corn Crops, says : — ■ 



I. Hordeum ustum or Ustilago Hordei, is that burnt 

 or blasted Barly which is altogether unprofitable and good 

 for nothing, an enemy unto corne ; for that instead of an 

 eare with corne there is nothing els but blacke dust, which 

 spoileth bread or whatsoever is made thereof. 



II. Burnt Otes or Ustilago Avenae or Avenacea is 

 likewise an unprofitable plant, degenerating from Otes, as 

 the other from barly, rie and wheat. It were in vain to 

 make a long harvest of such evil corne, considering it is 

 not possessed with one good qualitie. And therefor thus 

 much shall suffice for the description. 



III. Burnt Rie hath no one good property in physicke 

 appropriate either to Man, Birds, or Beast and is an hurtful 

 maladie unto all Corne where it groweth, having an ear in 



Naturalist, 



